scholarly journals Information-theoretic View of the Variation of the Gravitational Constant

Author(s):  
Subhash Kak

Many recent theories speak of the spatial and temporal variations of the fundamental “constants”, and experiments have been performed to determine the variation. It has also been proposed that the variation of these constants is related to the strength of the gravitational potential whose changes, therefore, assume special significance. Here we examine potential change in G from the information-theoretic perspective of noninteger dimensionality and determine a relationship with respect to time. We show that the rate of change using this method is of the same order as estimated using other approaches.

2021 ◽  
Author(s):  
Subhash Kak

Many recent theories speak of the spatial and temporal variations of the fundamental “constants”, and experiments have been performed to determine the variation. It has also been proposed that the variation of these constants is related to the strength of the gravitational potential whose changes, therefore, assume special significance. Here we examine potential change in G from the information-theoretic perspective of noninteger dimensionality and determine a relationship with respect to time. We show that the rate of change using this method is of the same order as estimated using other approaches.


Atmosphere ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 231
Author(s):  
Zhenghan Lv ◽  
Yusheng Shi ◽  
Shuying Zang ◽  
Li Sun

Over the past few decades, concentrations of carbon dioxide (CO2), a key greenhouse gas, have risen at a global rate of approximately 2 ppm/a. China is the largest CO2 emitter and is the principle contributor to the increase in global CO2 levels. Based on a satellite-retrieved atmospheric carbon dioxide column average dry air mixing ratio (XCO2) dataset, derived from the greenhouse gas observation satellite (GOSAT), this paper evaluates the spatial and temporal variations of XCO2 characteristics in China during 2009–2016. Moreover, the factors influencing changes in XCO2 were investigated. Results showed XCO2 concentrations in China increased at an average rate of 2.28 ppm/a, with significant annual seasonal variations of 6.78 ppm. The rate of change of XCO2 was greater in south China compared to other regions across China, with clear differences in seasonality. Seasonal variations in XCO2 concentrations across China were generally controlled by vegetation dynamics, characterized by the Normalized Difference Vegetation Index (NDVI). However, driving factors exhibited spatial variations. In particular, a distinct belt (northeast–southwest) with a significant negative correlation (r < −0.75) between XCO2 and NDVI was observed. Furthermore, in north China, human emissions were identified as the dominant influencing factor of total XCO2 variations (r > 0.65), with forest fires taking first place in southwest China (r > 0.47). Our results in this study can provide us with a potential way to better understand the spatiotemporal changes of CO2 concentration in China with NDVI, human activity and biomass burning, and could have an enlightening effect on slowing the growth of CO2 concentration in China.


2021 ◽  
Vol 3 (7) ◽  
Author(s):  
Alex Saturday ◽  
Thomas J. Lyimo ◽  
John Machiwa ◽  
Siajali Pamba

AbstractBackground Microbial water quality serves to indicate health risks associated with the consumption of contaminated water. Nevertheless, little is known about the microbiological characteristics of water in Lake Bunyonyi. This study was therefore undertaken to examine the spatial and temporal variations of faecal indicator bacteria (FIB) in relation to physicochemical parameters in Lake Bunyonyi. Result The FIB concentration was consistently measured during sampling months and correlated with each other showing the presumed human faecal pollution in the lake. The highest concentration values for E. coli (64.7 ± 47.3 CFU/100 mL) and enterococci (24.6 ± 32.4 CFU/100 mL were obtained in the station close to the Mugyera trading centre. On a temporal basis, the maximum values were recorded during the rainy season in October 2019 (70.7 ± 56.5 CFU/100 mL for E. coli and 38.44 ± 31.8 CFU/100 mL for enterococci. FIB did not differ significantly among the study stations (p > 0.05) but showed significant temporal variations among the months (p < 0.05) with concentrations being significantly high in wet season than dry season (U = 794, p < 0.0001 for E. coli; U = 993.5, p = 0.008 for enterococci). Spearman’s rank correlation revealed that FIB concentrations were significantly positively correlated with turbidity and DO concentration levels (p < 0.05). Approximately 97.2% of the water samples had E. coli and enterococci concentrations levels below USEPA threshold for recreational waters. Likewise, 98.1 and 90.7% of samples recorded E. coli and enterococci counts exceeding the UNBS, APHA, WHO and EU threshold values for drinking water. Conclusion The FIB counts show that the Lake Bunyonyi water is bacteriologically unsuitable for drinking unless it is treated since the FIB pose health risks to consumers. Besides, the water can be used for recreational purposes.


2003 ◽  
Vol 28 (1) ◽  
pp. 129-150 ◽  
Author(s):  
J.F. Lynch ◽  
A.E. Newhall ◽  
B. Sperry ◽  
G. Gawarkiewicz ◽  
A. Fredricks ◽  
...  

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
J. M. García-Torrecillas ◽  
M. C. Olvera-Porcel ◽  
M. Ferrer-Márquez ◽  
F. Rubio-Gil ◽  
M J. Sánchez ◽  
...  

2012 ◽  
Vol 22 (1) ◽  
pp. 95-105 ◽  
Author(s):  
Tatiane M. Gogola ◽  
Paulo V. Sanches ◽  
Éder A. Gubiani ◽  
Pedro R. L. da Silva

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